diff --git a/include/boost/geometry/extensions/contrib/ttmath_stub.hpp b/include/boost/geometry/extensions/contrib/ttmath_stub.hpp
index 009942979..fb5bf048e 100644
--- a/include/boost/geometry/extensions/contrib/ttmath_stub.hpp
+++ b/include/boost/geometry/extensions/contrib/ttmath_stub.hpp
@@ -1,8 +1,13 @@
 // Boost.Geometry (aka GGL, Generic Geometry Library)
 
-// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
-// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
-// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
+// Copyright (c) 2007-2015 Barend Gehrels, Amsterdam, the Netherlands.
+// Copyright (c) 2008-2015 Bruno Lalande, Paris, France.
+// Copyright (c) 2009-2015 Mateusz Loskot, London, UK.
+
+// This file was modified by Oracle on 2014, 2015.
+// Modifications copyright (c) 2014-2015, Oracle and/or its affiliates.
+
+// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
 
 // Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
 // (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands.
@@ -116,43 +121,18 @@ struct ttmath_big : ttmath::Big<1,4>
         : ttmath::Big<1,4>(v)
     {}
 
-    // needed since the binary operator+ needs to be defined
+    // unary operator+() is implemented for completeness
     inline ttmath_big const& operator+() const
     {
         return *this;
     }
 
-    // needed in order for the result of the addition to be a ttmath_big object
-    inline ttmath_big operator+(ttmath_big const& other) const
-    {
-        return ttmath::Big<1,4>::operator+(other);
-    }
-
     // needed in order to work with boost::geometry::math::abs
     inline ttmath_big operator-() const
     {
         return ttmath::Big<1,4>::operator-();
     }
 
-    // needed because unary operator-() is defined (above)
-    inline ttmath_big operator-(ttmath_big const& other) const
-    {
-        return ttmath::Big<1,4>::operator-(other);
-    }
-
-    // needed in order for the result of the multiplication to be a
-    // ttmath_big object
-    inline ttmath_big operator*(ttmath_big const& other) const
-    {
-        return ttmath::Big<1,4>::operator*(other);
-    }
-
-    // needed in order for the result of the division to be a ttmath_big object
-    inline ttmath_big operator/(ttmath_big const& other) const
-    {
-        return ttmath::Big<1,4>::operator/(other);
-    }
-
     /*
     inline operator double() const
     {
@@ -166,6 +146,29 @@ struct ttmath_big : ttmath::Big<1,4>
     */
 };
 
+
+// arithmetic operators for ttmath_big objects, defined as free functions
+inline ttmath_big operator+(ttmath_big const& x, ttmath_big const& y)
+{
+    return static_cast<ttmath::Big<1,4> const&>(x).operator+(y);
+}
+
+inline ttmath_big operator-(ttmath_big const& x, ttmath_big const& y)
+{
+    return static_cast<ttmath::Big<1,4> const&>(x).operator-(y);
+}
+
+inline ttmath_big operator*(ttmath_big const& x, ttmath_big const& y)
+{
+    return static_cast<ttmath::Big<1,4> const&>(x).operator*(y);
+}
+
+inline ttmath_big operator/(ttmath_big const& x, ttmath_big const& y)
+{
+    return static_cast<ttmath::Big<1,4> const&>(x).operator/(y);
+}
+
+
 namespace boost{ namespace geometry { namespace math
 {